Multicast routing

I'm testing QoS strategy on test network and I'm using wireshark to get result on my test scenario. I'm testing video broadcast across a network made with three 2600 router and 2 BPS2000 (Nortel switch) at the boundary.

Re: Multicast routing

Hi,

Before we go into the bowels of multicast routing the first thing we have to ascertain is that your source PC2 is actually using VLC to stream the video content to a multicast address. If it is then running wireshark on PC2 should show that it is sending information to 1 or more multicast groups [224.x.x.x - 239.x.x.x]. Can you confirm this?

Secondly, you need to confirm that the 3 2600 routers are PIM neighbours of each other. I'm assuming that the link between the routers are WAN links. In that case running show ip pim nei on router1 should show that router2 is its PIM neighbour, running show ip pim nei on router2 should show that router1 & router3 are its PIM neighbours and finally running show ip pim nei on router3 should show that router2 is its PIM neighbour. can you confirm this?

In order to force router1 to send the traffic to PC1 [your receiver] use ip igmp static-group . But apply this on the interface that is connected to the BPS2000(switch)that is connected to PC1. Then to confirm that it is correctly applied issue the following command show ip igmp group. This should show that the interface you applied the command to is a receiver/member of the multicast group. Make sure that you have no ACLs that may be blocking PIM on the routers.

You can then run show ip mroute on router1, router2 & router3 to show that multicast state is created. Unfortunately, trying to go into the interpretation of the output will make this post even lengthier. But suffice to say that on each of the routers you should see the source as PC2 and the OIL [out going interface list] as the interface towards PC2.

Re: Multicast routing

Hi cjnwodo

thank you for your response.

First, I confirm that VLC stream the video content to a multicast address.

Secondly ip pim nei give the good result on all the router.

Unfortunaltly when I start video streaming from PC2, transmission doesn't work. I can see activity on router1 (led blinks) but only on this one. I deduct that this router can't succeed to find out where it must route packets with 224.1.1.1 destination address.

You can find in attachment my network scheme and addressing and the running config of my three routers

Re: Multicast routing

Hi

Could you check if there is ttl setting for the video stream with the VLC software. You will need to make sure it has a ttl of at least 3 to reach PC1.

You should not need the "ip igmp join..." on R1 as this is pim dense mode so you should see the 224.1.1.1 group on all your routers anyway regardless of whether anything wants to receive the video stream.

Also could you confirm whether or not you have turned IGMP snooping on on the switches.

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